Microsoft today started rolling out what some are calling the “RTM” of Windows 10 today to both slow and fast ring Windows Insiders. You can download it now via Windows Update.

According to Gabe Aul’s post on Blogging Windows: “Over the past few days we’ve been preparing our release pipelines and processes, and this build is one step closer to what customers will start to receive on 7/29.”

Microsoft has stopped making new builds, and has not officially declared this the RTM. But, instead the company is making update packages for this build, 10204.

First, a quick peek behind the curtain: a trusted source at Microsoft has told me that the software giant has not signed off on Windows 10. That said, it has also stopped building new builds and is now busy building update packages for build 10240. Which suggests that Microsoft might not even declare RTM as they have in the past—i.e tie it to a specific build—but could instead declare RTM as this build plus certain critical updates.

Notice in the screenshot below that this build is called TH1 Core 10240 – which we assume stands for the “Threshold” codename for the OS.

While Microsoft is not officially calling this the RTM (Release to Manufacturing) it is in fact what will be going out to various vendors like Dell, Lenovo, etc.

However, from now until the actual release date on the 29th (and beyond), more updates and features will continue to be added.

Apparently there will not be ISO versions available for this version, but they should be coming after the official release.

We’re just downloading it now, and will let you know as soon as we are able. If you are an Insider, download the new build, and let us know how it goes for you in the comments below.